SINGLE-MODE EXCITATION IN THE SHALLOW-WATER ACOUSTIC CHANNEL USING FEEDBACK-CONTROL

The shallow-water acoustic channel supports farfield propagation in a discrete set of modes, Ocean experiments have confirmed the modal natu re of acoustic propagation, but no experiment has successfully excited only one of the suite of midfrequency trapped modes propagating in a coastal environment. The ability to excite a single mode would be a po werful tool for investigating shallow-water ocean processes, A feedbac k control algorithm incorporating elements of adaptive estimation, und erwater acoustics, array processing, and control theory to generate a high-fidelity single mode is presented, This approach also yields a co hesive framework for evaluating the feasibility of generating a single mode with given array geometries, noise characteristics, and source p ower limitations, Simulations and laboratory waveguide experiments ind icate the proposed algorithm holds promise for ocean experiments.